Field of the Invention
This invention relates generally to evaporative coolers and, more specifically, to apparatus and method for periodically refreshing the water used in an evaporative cooler.
An evaporative cooler is a cooling apparatus which operates by forcing air through pads which are saturated with water; the air is cooled by evaporation of the water from the pads. The conventional cooler includes a sump filled with water from which the water is pumped through tubing known as a spider, to a drip system at the top of the pads. The water drips down through the pads and the excess returns to the sump. Water is added to the sump to replace water lost by evaporation.
Although an evaporative cooler is generally an energy efficient, practical air conditioner, it has shortcomings which reduce its effectiveness and which make it less than totally satisfactory in use. The shortcomings relate to contaminants which collect and build up in the recirculating water. Air passing through the cooler pads carries dirt, algae, bacteria, and the like. Additionally, the water contains minerals which are left behind as the water evaporates. The dirt and minerals deposit on the pads, clog the pads, and reduce the cooling efficiency. Bacteria and algae multiply on the pads and in the sump, causing clogging and loss of efficiency. More importantly, however, the build up of such organic contaminants cause an unpleasant "fishy" odor which is transmitted to the cooled air.
Two methods have previously been proposed to reduce the problem of contamination, but they have not been entirely satisfactory. One method is to continuously bleed off a small amount of the water distributed by the spider. This is partially effective, but does not reduce large scale build ups of contaminants in the sumps. A second method is to add chemicals to the water to kill organic contaminants. The additives are expensive and have no effect on inorganic contaminants such as dirt and minerals. Also, the two methods cannot easily be combined because the chemical additives may be harmful to vegetation. The water bled off, if it contains additives, must therefore be carefully disposed of.
Accordingly, a need existed for means to solve the foregoing problems attendant with evaporative coolers which have not been satisfactorily solved by prior art methods.
It is therefore an object of this invention to provide an improved apparatus for exchanging the water used in an evaporative cooler.
It is a further object of this invention to provide a method for refreshing the water in an evaporative cooler.
It is another object of this invention to provide an improved apparatus for increasing the efficiency of an evaporative cooler.
It is yet another object of this invention to provide an improved method for operating an evaporative cooler.